The purpose of this study is to elucidate the metabolic fate of the B2-agonist drugs: aluterol and terbutaline. Both drugs are administered as racemates (50:50 mixtures of active and inactive stereoisomers). Whereas the main metabolic pathway is sulfate conjugation, the stereochemisty is unknown. The goal is to determine the stereochemical composition of the parent drugs and sulfates in urine, blood and platelets.